The present invention relates to door locks, more particularly to a structurally improved electromagnetic door lock in which the movable components are disengageable so as to save the electricity and to prevent the lock from the mechanical abrasion.
Prior art electronic door locks are most likely employing an electronic circuit in a conventional door lock to actuate the electromagnetic components therein on or to obtain the locking or unlocking of a door. Such door locks may be either unlocked manually or electronically by inputting a secret code on a keypad or an identification card inserting into a slot therein. Moreover, such door lock may connect with a security system for preventing from the burglary or recording the personnel entrance in a big firm.
However, once a secret code is inputted, the electronic circuit therein must supply continuously the electricity to the electromagnetic components in order to maintain the door lock in a state reliable to unlock at anytime, therefore, causing the electric consumption; Besides, the electromagnetic components therein are engageable with each other, it is unavoidable that they will be abraded under frequent pushing and budging, thus, reducing the reliability and the durability of the components.
Furthermore, if such door lock employs an electric-saving device such that the electricity may cut off after every unlocking movement and the door is automatically locked after the passage of a person, it is unapt for a big place such as an office or a factory where the personnel entrance are very frequent.